Printing press drive control system



May 5, 1964 J. E. BLACK PRINTING PRESS DRIVE CONTROL SYSTEM 7 Sheets-Sheet 1 Filed Sept. 14, 1959 mmf Av 335.3 `w5o oww May 5, 1964 J. E. BLACK 3,132,295

PRINTING PRESS DRIVE CONTROL SYSTEM Filed Sept. 14, 1959 7 Sheets-Sheet 2 M O l7'/ NS /N DE EES sW/rf/f o V CONTfOL GO- /V INVENTOR.

May 5, 1954 J. E. BLACK 3,132,295

PRINTING PRESS DRIVE CONTROL SYSTEM Filed Sept. 14, 1959 7 Sheecs-Sheetl 3 May 5, 1964 J. E. BLACK PRINTING PRESS DRIVE CONTROL SYSTEM 'T Sheets-Sheet 4 Filed Sept. 14, 1959 NWN UNG .05

AOP@

4 mmm m mmm.

www;

w www @EN May 5, 1964 .1. E. BLACK PRINTING PRESS DRIVE CONTROL SYSTEM Filed Sep. 14, 1959 mw E mw. E am Il Jz. l I l, NN l www f @vw vif o 1| |11 U O @Al w f flu @www BY S'MM WSW May 5, 1964 J. E. BLACK 3,132,295

PRINTING PRESS DRIVE CONTROL SYSTEM Filed Sept. 14, 1959 '7 Sheets-Sheet 6 2&7

INVENTOR.

v 202 D l jow gci v BY @7M/"llega May 5, 1964 BLACK 3,132,295

PRINTING PRESS DRIVE CONTROL SYSTEM Filed Sept. 14, 1959 7 Sheets-Sheet 7 @bbw/nega United States Patent O 3,132,295 PRINTING PRESS DRIVE CONTROL SYSTE John E. Black, Catlin, Ill., assignor to Electric Eye Equipment Company, Danville, Ill., a corporation of Delaware Filed Sept. 14, 1959, Ser. No. 839,892 6 Claims. (Cl. S18-163) This invention relates generally to printing press drives and more particularly is concerned with a system in which the source of rotary power comprises a D.C. motor and which has lnovel and improved control means therefor.y

The type of presses with which the invention is concerned comprise large, high speed installations in which printing pla-tes `are applied to notary cylinders or the matter to 4be printed is etched into the cylinders, and the cylinders are inked `and rotated relative -to elongate moving webs of paper to which the impressions carried by the printing cylinders are applied. Such presses produce newspapers, color supplements for newspapers, magazines and the like at web speeds which approach 2G00 feet per minute, and usually include equipment which is required to trim and cut, fold and assemble the resulting products, all in perfect synchronismwith the printed impressions. Obviously color presses are .required to print upon the web with as many as four different impressions.

The requirements of the drive and control for such presses, exclusive of requirements of registrati-on of impression and lateral posit-ioning of the web are manifold.

Such requirements have in the past rendered drives and controls complex, expensive, difiioult to install and maintain, and subject to many other disadvantages. Not the least of these disadvantages were the almost universal use of switches, relays and controls depending upon the inter-engagement of electrical contacts, either Iby impact or wiping. The diiculties inherent in depending upon mechanical engagement of electrical contacts `are wellknown and these include sparking dangers, high costs of maintenance and repair, unreliability, expensive original cost, etc.

One of the important objects of the invention is the provision of a system whose nature is such that there is no need for mechanical engagement between electrical Contact means, the control being accomplished with a minimum of moving parts and through the use of completely encapsulated static control elements of the Vtype described in Rainey Patents 2,717,965, 2,770,737,

2,783,315 and the like.

yIn order .to provide a basis for a -full understanding of .the invention,'the requirements of press drives will preliminarily be discussed, prior to entering upon a detailed explanation of the preferred embodiment of the invention. In considering these requirements, it should be appreciated that the most important objects of the invention are concerned with mee-ting Ithese requirements in a manner which is more eiiicient, simpler, more economical, yand more effective than previously believed possible. These general objects `are stated at this point of the discussion so that they may be ykept in mind as an important purpose or the invention, there being other objects speciiically directed to some of the details ofthe drive and the controls which will be stated hereunder.

One of the most important factors which must be also borne in mind is that in previous press drives the control has not been as complete as herein, this being most important to ilexibility of the system Iand eiciency of its use. This increased degree of control extends over the entire lrange of speed of the drive and is what makes this system so desirable. Other press drives provide control, but not to .the same degree, and hence provide many of the disadvantages which have caused difficulties with previous apparatus.

yice

The requirements of press drives may be generally considered ascomprising the following:

(a) The typical newspaper installation may have from one to several press units, each of which may have from two to ten heavy motors driving the various printing rolls or cylinders and folding equipment, all of the motors being coupled for rotation in unison. The movements ofthe press which will be described hereinafter must take into consideration overcoming inertia and .frictiom and the proper application of power for moving and stopping all of these motors andy equipment operated by them in accordance with predetermined programs or commands controlled by the prcssman.

(b) The tensioning of the web must be controlled at different opera-ting conditions of the press.

(c) The registration and lateral adjustment equipment must be coordinated with the operation of the press so that the control means `operated by the registration equipment does not interfere -with the normal proper functioning of the press during certain conditions of operation thereof,

(d) The characteristics of the particular drive motors operating at various speeds must he built into the control equipment so that the requirements of power are niet for the various conditions of movement of the press.

(e) The Lvarious safety factors which have become accepted as vital topress operation must be built into the control either for completely manual or completely automatic control.

(f) The control must provide for the following conditions which are concerned with eicient and practical operation of the press:

(l) Safe-ready (2) -lnch (3) Slower (4) Faster (5) Stop (6) Automatic Decelerate (7) Automatic Accelerate (8)A Detecting The sate-ready condition is one in which the speed of the press is xed or clamped at a given rate by means of a manually operated switch. From this condition, the press speed can be decreased to zero but cannot be raised. From any speed to which the press has been decreased, under safe-ready condition, the press can only be decreased in speed or stopped. Once stopped, on safe-ready condition the press cannot be started until the condition is manually removed.

The safe-ready condition is required for safety of personnel who may Ibe working on the press and wish to keep the same from running, or where a condition is discovered which is to be corrected while the press is running at a certain slow speed, it being desired that the speed be not increased by operation of any other control means. y L

The incr condition is one in which the press is run by manually closing a switch, but at a very'y slow rate, and only so long as the switch is closed. This is required =for set-up work, for testing, -for accurate positioning of parts of the press for maintenance and repair, and the like. The press can be operated to move the web therethrough in very small Vincrements through this condition. This condition can be used also to permit the press to run for a time prior to high speed, to thread the same, to check impression and the like.

The slower condition is one in which the speedof the press is to be decreased from a high rate by manually operating a control element, such as a switch. ln the system of the invention, deceleration occurs automatically at a predetermined rate which is built into the system.

`being performed. operator presses it once, releases it, and the acceleration The aster condition is one in which the speed of the press is to be increased from Ia lower value to maximum, through the manual operation of a control element, such as a switch. "Ihe acceleration occurs at a nate which is built into the system and in the apparatus of the invention, one which is different from the deceleration rate or slower condition.

In the cases of both conditions described above, the speed of the press maybe chosen and fixed at any desired value by the operator merely by tde-activating the particular control element when the speed has been reached at which it is desired to maintain operation of the press.

The stop condition is an emergency measure and is one in which it is desired to bring the press to a full stop in as short a time as possible, 'and without damaging any parts of the press or the control system.

yThe automatic deceleration condition is one in which, through the actuation of a suitable control element such as a manual switch, the press speed is decreased along a predetermined function of deceleration to a particular speed somewhat daster than inching, and the press remains at that speed, as determined by suitable limit switch means. ln most presses when a new roll of paper is to be connected to the web, the press is slowed down, the reel carrying the new roll is rotated ata circumferential speed which is substantially the linear speed of the web as it is being stripped from the expiring roll, and at a suitable instant, the new end is pasted to the moving web .which immediately commences stripping the paper from the new roll. The speed at which this is done is controlled by the said limit switch means.

The automatic accelerate condition is one in which by manual operation of a suitable control element such as a switch, the press lwill increase its speed to a maximum pre-set speed point automatically, along an acceleration function substantially identical with that referred to in connection with the faster condition described above. Maximum achieved speed here is con-trolled by ia suitable limit switch fwhich is adjustable to any predetermined value. The diierence between this condition and the faster condition is that the acceleration caused by the faster condition occurs only so long as the control element is actuated, that is, so long as the operator holds the switch closed, for example. In automatic acceleration the actuation of the'control element starts the cycle and the drive accelerates without any further function If the control element is a switch, the

automatically occurs until the pre-set maximum is reached.

The detecting conditions are provided through the medium of Iautomatic controls which are for the purpose of establishing the stop condition above described if the web breaks or other similar contingency arises. For example, there maybe a normally open switch riding the web which is closed if the web should discontinue through breakage or the like.

(g) Several other requirements of control and drive might be included in this discussion, such as for example, the basic need for turning the power on and off, operating the braking lmeans for stopping the motors, switching various parts of the circuits into and out of the system, and the like.

A control system and drive must provide for all of these conditions, and the invention herein does so in novel and improved manners.

lt has long been known that the best control of printing press drives is achieved through the use of drive motors operating on direct current. Since power companies have been supplying alternating current power only' for the past several decades, alternating current drives have principally been used. The disadvantages of such drives are well-known, and include many basic difculties which are not capable of being overcome without going to direct current motors. Alternating current motors operate at high eiciency only between about 90% and 100% of maximum speed, and hence it is necessary t have separate drive systems for low speed operation such as the inching condition described above. Alternating current motors do not have dynamic braking characteristios inherent in direct current motors, land hence separate braking systems are required. In alternating current motors, speed varies with load, `and horsepower varies with speed, hence variations in press operation such as impression, inking and the like will aiect speed regulation. Also, if the motor is overloaded, reduction of speed will further overload the motor, while in direct current motors the overloading of the motor is automatically obviaited by the motor slowing downitself. Another bad feature of alternating current motors is that for all speeds below maximum, the unused energy must be dissipated in the form of heat, either through a secondary resistance bank, eddy-current clutch or similar device. There are switching problems, heating and Ventilating problems and the like.

Some eorts have been made since the development of large water-cooled, mercury-arc rectifier tubes to build press drives which utilized direct current motors in press drives. These systems had disadvantages which have been overcome in the present system, as well. These disadvantages were concerned with the complex circuitry, the need for cooling systems for the tubes, need for large space in control rooms, high cost, etc.

The present invention teaches a system which, in addition to overcoming the disadvantages of the drives which use alternating current motors, also comprises a substantial improvement over the systems which were based upon the use of mercury-arc reotiers to change the alternating current to direct current.

In the instant invention, the source of rotary power for the press comprise direct current motors, as previously stated. The speed of a D.C. motor can be Controlled by varying the magnetic iield which is to be cut by the conductors moving relative thereto, the ampereturns of the conductors, or by varying both. As known, the magnetic field is varied by varying the voltage applied to the iield winding, and the ampere-turns of the conductors is varied by varying the current applied to the armature. Hereinafter reference made to the lield or armature of the D.C. motor will concern only the electrical nature thereof, it being immaterial which is the rotor and which is the stator.

The power requirements of the eld and armature of a relatively large D.C. motor may be and usually are supplied by ditferent sources, such as for example-a typical installation used` 460 volts A.C. three phase power suitably rectified for the armature, and 240 volts A.C. suitably rectified for the ield.

In the embodiment describedherein, three phase power is applied through saturable core reactors, which operate into rectifying means connected to the armature. The saturable core reactors are controlled by D.C. signals applied to the windings of the reactors, and the signals are obtained in a novel manner as will be described.

The single phase power is also applied through a saturable core reactor whose control winding is energized by a variable signal obtained also in a novel manner as Ywill be described, the output signal being rectified and applied as a voltage'across the eld winding.

One important object of the invention is the provision of a novel method for varying the speed of the drive motor between minimum and maximum values through the establishment of certain conditions of armature current and field potential and the provision of novel means for programming these conditions.

In connection with the means above referred to for programming the conditions for varying the speed of the drive motor, the invention contemplates the use of control means driven by a pilot motor. The use of a pilot motor perse in printing press drives and their controls is well-known, but heretofore such pilot motors have driven electrical contact means, such as plates having contacts or terminals thereon moving relative to other contacts, terminals or Wipers to establish, change or break an electrical circuit mechanically.

In the invention herein, and it is an important object to achieve such structure, the pilot motor changes the rotor-stator relationship of one or more rotary transformers the output of which may be modiiied by amplitication or the like to form signals for controlling the saturable core reactors above mentioned. The degree of rotation of the pilot motor is converted to any desired other degree of relative rotor-stator rotation to provide for desired and predetermined programming, the provision of structure to enable this to be achieved being an additional object of the invention.

The pilot motor in addition, according to the invention, accomplishes other switching functions cooperatively related to the system and certain parts thereof, in order to enable the requirementsoutlined above to be metin an etiicient and desirable manner.

The invention also contemplates the use of the static control devices referred to above as typified by the Rainey patented structures, which achieve conditions amounting to the making of logical decisions, which formerly were required `to be made by unreliable relays or similar mechanically moving devices unsatisfactory and critical in operation. The inclusion of these static control devices in the system renders the system reliable, compact and foolproof, but it is also desired to point out that important features of the invention are of great advantage in systems which do not necessarily use static control devices, but which utilize conventional relays and the like in the control of the drives. This will be brought out hereinafter, and especially Will be emphasized in the claims.

As the detailed description proceeds, many important otherobjects of the invention will become apparent to those skilled in this art. The invention is believed to be a complete and radical departure from all prior systems and methods of control, not only system-wise but also `component-wise in that structures are used as components of the overall system which yare novel and unobvious in and of themselves. Such components, as well as sub-combinations of the same with one another and with known structures and means, are considered to be included in the inventive concepts as delineated hereinafter and in the claims, and in certain instances, such inventions may be applicable in other iields which may be mentioned in passing. The basic purpose for the invention herein, however, and the application for which the `same is specically intended togive the maximum of advantages and benefits, is to control and energize the drives for printing presses, and hence, the description and illustrations concern only such applications. So far as practicable, the drawings will illustrate the preferred embodiments of the invention and the parts thereof believed to be inventive collaterally, using known and conventional symbols, diagrams and schematic mechanical and electrical representations. Certain important structural features will be illustrated specifically in order to show'a preferred manner of constructing the same. The diagrams representing functions are intended to cover typical conditions and substantially correct data, although it is to be understood that each installation will vary somewhat depending upon many factors which are known to artisans skilled in this iield.

In the drawings:

FIG. l is a general block diagram of a press drive or system constructed in accordance with the invention.

FIG. 2 is a graph showing the acceleration and deceleration curves of the drive plotted against time and cam rotation.

FIG. 3 is a circuit diagram illustrating the armature and field control elements which are shown in block diagram in FIG. 1.

FIG. 4 is a chart showing the programming of auxliliary switches operated by rotation of the pilot motor.

FIG. 5 -is a schematic diagramk of the ,master control unit of the press drive showing the static control elements circuitry.r

fFlG. `6 is a side elevational view of the Vassembly of the pilot motor, rotary transformers and the drives for the various switches actuated thereby.

FlG. 7 is a diront elevational view of the assemblage with the hand wheel removed.

FIG. 8 is a sectional view through the pilot motor drive taken along the lline tl-S of FIG. 6 and in the indicated direction.

FIG. 9 is an enlarged fragmentary sectional view of the left hand end of the pilot motor assemblage of FIG. 6.

FIG. l() is a diagrammatic -view of a basic printing press installation using a single drive motor and control.

FlG. lvl is a perspective view of a pair of cabinets mounting the supervisory controller of a folder and a' unit controller Ifor a single motor.

FIG. 12 is a diagrammatic view of atypical newspaper press having a unitized drive accord-ing to the invention, in which there is a single motor for each press unit and folder all Idriven in synchronisrn and controlled from an assemblage of controllers such as shown in FIG. 11.

Referring now to FIGS. l, 2 and 3, the general arrangement of the press drive and control therefor will be eX- plained. Perhaps the heart of the system comprises a pilot motor which is energized by two windings and which is shown schematically `at 5G in the v:block diagram of FIG. l. This pilot motor drives two rotary transformers, comprising the armature control transformer 52 and the field control transformer 54 to provide the necessary control forthe press drive motor '55,the armature windings being designated Sti andthe iield winding or windings 57, 55S and 59. lhe rotation of the pilot motor 5) also operates certain switches on a program which is schematically shown in the graph FIG. 4. The series field ,winding is 58 and the commutating field winding is 59.

As previously mentioned, pilot motors per se have been used in other press drives and controls therefor. These prior pilot motors have lbeen operated by push-buttons and other :directly connected manual switching devices with extensive use of latching relays ide-energized when lthe pilot motors achieved `certain positions to accomplish certain functions. These pilot motors drove positioning plates operating in yconjunction with contacts .which were opened, closed, wiped, etc. in order properly to program the necessary operating relays. De-energization of the latching relays was usually accomplished through contacts provided in the plate driven by the pilot motor. Such latching as done was only where automatic switching was accomplished, since most of the functions desired were accomplished through the use of manual push-buttons operating relays and the like mechanically actuated switching gear.

` So far as known, there has been no arrangement in which the pilot motor was driven through completely contactless circuitry for all phases of operation, and in turn drove yrotary transformers which programmed the energization of the drive motor or motors in response to the predetermined programming built into the system.

The pilot motor Si) is caused `to rotate by signals applied thereto by the static 'control elements system, which is generally designated 60. The system 60 is illustrated in some det-ail in FlG. 5 but for this general explanation, sutiice it t-o say at this point that the signals which are produced by the system 6d are obtained by changing the volts A.C. source energizing the system 6G to suitable pulses and currents. This is accomplished through the medium of various manual controls such as push button switches at one or more stations, such as for example a primary group of push buttons k62 on a supervisory control unit located at a folder,y and a secondary group of push buttons (ad at a press unit. ln addition, certain automatic controls are arranged to affect the operation of the system, such as detector means 66 which may operate for example in connection with web-severing signal producing switches or other emergency signal producing de- Each of the rotary transformers 52 and 54 has a primary Winding and a secondary winding, one of which is a stator and the other of which is the rotor. The primary windings are 78 and 80 respectively, and the secondary windings are-82 and 84 respectively. The rotors or both transformers 52 and v54 and several cams for operating certain limit switches are rall `driven by the pilot motor 50 in a manner which will be described -in connection with FIGS. 5, `6, 7, 8 :and 9.

The power for the `drive system is obtained from a 460 volts, three phase, 60 cycle source 70, and the various requirements of voltage are transformed rfrom this source. The source has three lines 71, 72 and 73 which are taken through three circuit breakers 74, 75 and 76 to the lower voltage transformers, but are connected directly to the components of the system which use the full voltage. This is shown in FIG. 3.

One step-down transformer 88 has its primary winding 86 connected across the breakers 74 and 75 and provides 230 volts A.C. at its secondary 90 for energizing a saturable core reactor 92 in the control channel for the armature 56. Another step-down transformer 94 has its primary winding 96 connected across the breakers 75 and 76 and provides 280 volts A.C. at its secondary 93 for energizing a saturable core reactor 100 which is in the control channel for the field `58. Still another step-down transformer 102 is connected across breakers 74 and 7-6 to reduce the voltage to .120 volts A.C. for the magnetic amplifier 104 which is in the armature control channel, for the magnetic amplifier 106, for the primary 78 `of the. armature control rotary transformer 52, for the primary winding 80 of the field control rotary transformer 54 and `for any other components not shown which require ordinary 120 volts A.C. The voltage input for the primary winding 78 of the rotary transformer 52 may be regulated in which case a constant potential transformer 103 whose primary winding 105 is connected across the secondary 101 of transformer 102, and whose secondary 107 is in parallel with secondary 78.

The main power line 70 is the source of power for the armature 56, `and its conductors 71, 72 and 73 are connected directly through the circuit breakers 108, 109 and 1110 and line contactors 111, 112 and 113 to the saturable core reactors 114, 115 and 116 respectively which provide the necessary power.

Considering only the general block Idiagram of fFIG. 1 the overall operation of the press drive system may be discussed, without regard to the nature of the control signals.

The basic control channel, that is, the path of signal transmission, for the operation of the armature 56 follows to the right of the rotary transformer 52, and is symbolically indicated by the lines between the block elements, which are designated for convenience AC-1 to AC-8 inclusive, signifying armature control channe Likewise, the basic control channel for the operation of the field is shown symbolically by means of the lines FC-l to FCw4 inclusive, signifying field control channel. These lines do not necessarily represent conductors or leads but are merely diagrammatic to clarify the paths of command or variation signals. They represent signal transmission by any of different means.

Examination of the block diagram will indicate at once that the power supplied to the respective parts of the drive motor S is obtained in different manners. The armature 56 requires large amounts of power, and hence the control channel provides a signal which serves in eect for valving the power provided directly from the high voltage three phase line 70. In the case of the field 57, however, the power requirements are substantially less,

.and hence the power source is the 280 volts A.C. transformer 94 which is controlled. Note that the control channel for the field extends only up to the saturable core reactor 100.

The speed control achieved in the drive motor 55 is obtained, as will be explained in connection with FIG. 2, by varying the excitation of the armature and field respectively. The rotational aspect of the windings of the transformers 52 and 54 provides this Variation.

Considering first the armature control transformer 52, its output is an A.C. signal which is transmitted by the path Afl-1 to the rectifier 118, which converts the signal into a direct current applied to the control windings of the magnetic amplifier 104 along the path AC-Z. The power applied directly to the magnetic amplifier 104 is varied according to the signal in path AC2 and the output from the magnetic amplifier 104 is applied through the path AC-3 to the rectifier 120 to the high power saturable core reactor 92 by way of the path AC-4. This reactor 92 provides the necessary powerto control the large reactors 114, 115 and 116. Its output at AC-S is applied through the rectifier 122 and the path AC-6 to the control windings of the reactors 114, 115 and 116 in series. These large reactors produce an A.C. output which is rectified in rectifier 124 and applied to the armature 56 as a D.C. voltage.

Considering next the field control transformer 54, its output is applied along path FC-l to rectifier 124 so that the magnetic amplifier 106 received a D.C. control signal along path FC-Z. The output of the magnetic amplifier 106 is A.C. and hence requires rectifying to be used as a control voltage for the saturable core reactor 100. The signal from amplifier 106 is applied by way of path FC-3, rectifier 126 and path FC-4 tothe saturable core reactor 100. The output from the saturable core reactor is rectified at the rectifier 126 directly to the shunt field 58.

Each of the armature and field has a feed-back path to its respective magnetic amplifier. The armature 56 has the feed-back path PBA which is shown in FIG. l, and the feed-back path for the field 57 is shown at FBF.

The above described system is readily understood, the armature control transformer 52 serving to vary the ampere-turns of the armature windings 56, and the field control transformer 54 serving to vary the magnetic eld produced by the field windings 57, the combination of these two resulting in various speeds of the motor 55. The rate at which the speed changes, either to speed up or slow down, can be altered by changing the combinations of these two control conditions and the ease with which this is done provides the great flexibility of the system.

Much of the detail of the actual structure is not shown in FIG. l, but a considerable portion is illustrated in FIG. 3. The components which are not shown in FIG.1 include the dynamic braking means, series field windings 58 and 59, regulation means for adjusting the system to load changes, etc.

The detailed explanation of the armature and field control circuit follows:

Starting with the signals which comprise the outputs of the rotary transformers 52 and 54, in each case the output is a variable A.C. voltage the amplitude of which depends upon the relative dispositions of the rotors and stators with respect to one another. While the electrical circuits of the respective transformers are independent, the rotors are both rotated by means of mechanical couplings connected with the same shaft driven by the pilot motor 50 (not shown on FIG. 3) but the couplings provide desired dispositions in accordance with predetermined characteristics desired of the press drive motor. The rotors are not ganged in the ordinary sense understood, but are driven together, and hence the symbolic arrows representing variable coupling are connected by a broken line.

The secondary windings 82 and 84 respectively provide outputs .that are connected across full-wave bridge rectiiers 118 and 124 respectively. Full wave rectied current appears at the output terminals of each bridge, the amplitude again being dependent upon the respective transformer coupling. The signals which are produced in the respective channels are the speed signals and they are referred to as pattern signals since the speed curve of the press drive motor is expected to follow a predetermined pattern which is dependent upon the amounts of respective armature and field signals yand their relations to one another. The amount of pattern signal is adjusted in each case by means of a variable resistor 131 and 132 respectively, and some of the ripple is removed by lilter choltes 133 and 134 so that the input to the magnetic amplifiers is fairly smooth DC.

The magnetic amplifier 164 has four windings, which are designated 136, 138, 140 and 142. The winding 136 is the main control winding which is energized by the output of the rectiiier 118. Winding 138 is a feed-back Winding which adjusts the output of the magnetic amplilier 164 for changes in load to good regulation characteristics. The winding 1d@ is the bias winding, by means of which the operating point of the characteristic of the magnetic amplifier is determined. The A.C. voltage from the secondary winding 101 is dropped through voltage divider 144 which includes a variable resistor by means of which any desired AC. voltage may be applied across the rectier 146 and the DC. output connected in series with said bias winding 140 and a current-limiting resistor 143. The winding 142 is the output winding of the magnetic amplier and, as seen, a pair of self-saturating rectiers 151) is connected in this Winding,.with the A.C. voltage supply having one side thereof connected to a terminal 151 between the rectiers 150.

These self-salturating rectiers provide a conducting path for the ilow of current in the forward direction through the output windings and block the supply voltage in the reverse direction. The particular circuit is a socalled full-Wave bridge circuit, the output of which is an A.C. signal, but since the load in this ca-se is a saturated core reactor 92 which requires a DC. control signal, the magnetic @amplifier is followed by the full-wave bridge rectilier 12). The second side of the A.C. supply is .connected to the terminal 152 of the rectifier 120, the

other terminal 153 being connected to the both ends of the output Winding 142.

The D.C. output of the rectifier bridge 12) is applied to control winding 154 of the saiturable core reactor 92 through variable resistor 156. The output of the rectifier 120 is lalso shunted by a variable resistor 157, and both of the resistors 156 and 157 have a plurality of taps with a wiper arrangement that can connect opposite taps of the respective resistors. These taps are chosen so that lthere is a particular tap yfor the number of motors which will be controlled by the system.

Nothing has been said concerning the use of more than one motor in the drive, butk it will be understood that the minimum number of motors that will require to be controlled and operated by the same master control is two, comprising a folder and a unit. The usual requirements :of a press drive for a normal installation may run from one to .as `Inany Ias ten units. Certain portions of apparatus are duplicated in each rnotor, and all of the motors are mechanically coupled together with clutches which can be `fle-coupled to use only the number desired. The portions of the apparatus to the right of the path AC-6 are repeated for every drive motor, and hence the signal from the rectiiier 122 will be applied to as many motors as used. The addition of parallel loads results in more current being drawn from the control channel, for every condition of operation, land hence there must be some compensation yfor such variations. rlhis is furnished by the resistors 156 and 157 and their rotative Wiper engaging the various taps. A similar arrangement is procontacts (see 324, FIG. 5) and must be closed for they motor to operate; 163 are motor transfer switches whose purpose is to enable manual disconnecting of the motor from the circuit; the contacts 164 shunting each of the output windings 165, 156 and 167 comprise switches which close when the base speed has been reached (as Will be explained below) so that there is no reactance and no power loss because of the inclusion of the output windings in the circuit to the larmature 56. A thyrite protective resistor shunts the circuit. Note that the output of the rectifier bridge 122 may be applied to other motor control circuits, as indicated at 169;

The three phase power from the source 75 is applied and controlledv through the saturable core reactors 114,k

and 116 to high current-carrying capacity reocihers to the armature 56 and the field windings 58 and 59 which are in series with the armature. The three-phase fullwave rectifier designated 124 is formed or" 24 rectier elements of the dry type, providing the DuC. output at the output terminals 171B and 171. The dynamic brake resistor 172 is connected across the armature and series iield windings to enable the ymotor 55 to be changed into a generator when the contacts 174 are closed and produce bucking linx tostop itself. 175 is an ammeter shunted in the lead 171. Various fuses and the like are not numbered.

Note that there is a series of resistors which shunt the windings 56, 58 `and 59. The entire arrangement cornprses a regulating bridge in Iwhich 17) and 171 are one pair of terminals, and 176 and 177 are the other terminals. Resistors 178, 179 and 18@ balance the resistance of the windings on the other side of the bridge. Terminals 176 and 177 connect through a variable resistor 182', switch 1S4 and the lter choke '185" to the winding 13S. The values of the bridge are chosen so that when the load on the motor varies causing current change in the series and commutating liclds 53 and 59, or the speed varies causing changes in the current flow of the armature, there will be an unbalance 4in thebridge and a signal `applied to the feed-back winding 138 to cornpensate for the change in load; The bridge values are adjusted for a condition of normal lload resulting in no output from the bridge. Thus, the regulation of the motor 55 is automatic for any setting irrespective of change of load and speed.

The iield control channel is similar to the armature control channel except that less power is handled. -The i pattern winding of the magnetic amplifier 196 is designated 1S1, and the amount of signal to the said winding is controlled by the resisetor 132. 'llhere are two additional con-trol windings 182 and 153, the bias Winding 184 and the output winding 155. The manner of biasing the magnetic amplifier, applying the A.C. input `and rectifying the output are substantially the same as in the case of the magnetic amplifier 1114 and hence similar characters :of reference are used for equivalent components, although primed. The method of adjusting the output for different 4loading because of the addition of motors is also the same, the double-ended wiper of the resistors 156 157 `being ganged to that of the resistors 156 and 157.

The output of the rectifier 126 is applied tothe input or control winding 154 of the saturable core reactor 100 which has a slightly greater capacity than the reactor 92 because the output of the saturable core reactor 100 is across these terminals as are the leads 189 and 190 which have resistors 191 and 192 in series therein. This a feedback path to the magnetic amplifier 106 being connected in series with the control winding 183 and a filter choke 193. Motor transfer relays i194 are provided as well as connections 195 to other motors. A thyrite protective resistor shunts the field winding 57.

A novel arrangement provides constant braking irrespective of speed by field control of the shunt field. A variable resistor 196 shunts the dynamic braking resistor and a feedback channel is provided by way of the leads 197 and 198 through series resistors 199 and transfer switch 200 equivalent to switch 104 and ganged therewith, to the control winding 102. Variations in speed will result in signals to the control winding 182 providing more or less shunting field to give constant braking. When the counter due to braking in the armature windings 58 and 59 is high, there will be a control signal applied 'to winding 182 which reduces field flux to smoothen the braking effect. effect.

It will be recalled that the signals produced in the Lower counter EMF. has the opposite channels controlling the field and the armature cooperate to provide the pattern signals to produce the desired speed characteristics of the motor 55 for Various conditions of operation. The acceleration and deceleration curves of FIG. 2 are not intended as limitations, but could be considered as typical for a given installation, varying from installation to installation depending upon the requirements, equipment, etc. These curves are plotted with coordinates that represent along the X-axis cam rotation in degrees, and two separate time axes, measured in seconds; along the Y-axis rotation of the drive motor 55 in r.p.m., which may be translated into newspapers per minute, feet per minute or the like.

By way of overall explanation, this diagram represents the speed that can be expected from the drive motor for any given rotational aspect of the cam shaft of the drive motor 50 during either acceleration or deceleration command signals. The control system 60 applies suitable signals to the motor 50 which moves to a particular position at a controlled speed. The detailed explanation of the curves of FIG. 2 will be more easily understood if one can picture in general terms what is happening mechanically in the apparatus shown in detail in FIGS. 6 to 9 inclusive. The detailed explanation will be undertaken later.

The motor 50 rotates a shaft 201 which has cams 203 and 205 affixed thereto so that rotational aspect of the shaft 201 represents as well rotational aspect of both cams 203 and 205. Each cam drives a follower 207 and 209 respectively which causes rotation of the shafts 211 and 213 of the rotary transformers 54 and 52 respectively. Thus, it can be deduced that the rotational aspects of the respective transformers 52 and 54 can be chosen independently and built into the apparatus through choice and design of the contours of cams S and 203, and the connecting linkages. A given position of the shaft 201 represents two conditions of coupling between the respective windings of the transformers 52 and 54 and hence also represents two conditions of energization of the armature 56 and field winding 57 of the motor 55.

Alluding once more to the explanation of the curves of FIG. 2, the base or X-axis scales are designated 214,

` 215 and 216. The scale 214 represents the rotation of the shaft 201 in degrees and it will be seen that it is desired and intended that the drive motor 55 will be able to vary its speed from a stand-still to maximum for a half revolution of the shaft 201. The speed in r.p.m. is scaled at 217 on the Y-axis, on the right hand side of the graph. The scale 215 is the time scale in seconds, when the motor speed is increasing from minimum to maximum; the scale 216 is the time scale in seconds when the motor speed is decreasing from maximum to minimum; die curves 21S and 219 represent the acceleration-deceleration curve and the stop curve respectively.

The speed of the particular motor whose characteristics are graphed varies from zero to 2000 r.p.m. and this latter speed is reached when the shaft 201 has rotated 180 dpring acceleration or manual increase of speed. The degree of rotation could of course be any amount chosen and designed into the apparatus. The time elapsed during this rotation is 60 seconds. Deceleration occurs along the same line 218 but in a matter of 40 seconds, since it is usually easier to decelerate than accelerate, and more desirable to do so faster. The stopping of the motor quickly, as for an emergency occurs along the line 219 with reference to the scale 216 and hence in a time of ten seconds.

The speed characteristics could be graphed against the rotational positions of the rotary transformers, but timewise this would be complex and the interpretation would be confusing because of the variations throughout rotation of the shaft 201 by the pilot motor 50.

The curves shown are typical as stated, and must be computed for each installation. They will not necessarily be straight lines, but could curve in various manners, depending upon the motors, the loads, etc. Also the motor circuits may vary from installation to installation. In this instance, as seen from an examination of FIG. 3, the Ymotors are connected series-shunt, in a manner known as stabilized shunt wound.

The motor 55 of the installation chosen as typical has a base speed which is marked along the line 21S as the point 220, representing a speed of 1150 r.p.m. This base speed is the `condition which exists when the field and armature are at maximum excitation, represented by maximum signal output from the secondaries of both of the rotary transformers 52 and 54 with maximum pattern signals in the armature and eld control channels. The cam shaft 201 of the pilot motor 50 at this point has rotated through about from its zero position. Speed is increased from the base speed 220 by decreasing the excitation of the field 57 so that at the maximum speed of 2000 r.p.m., field excitation is at a minimum and armature excitation is at a maximum. From the base speed to the maximum speed, that is, in moving along the line 218 from the point 220 to the point 221 the armature excitation remained at maximum while the field excitation was decreased. During this period of increase of speed the cam shaft 201 rotates through 75 and the rotary transformer Se will have its coupling changed, but the coupling of transformer S2 will remain constant. In terms of mechanical linkages, the follower 209 would be on a dwell portion of the cam 205 of substantially constant radius.

The other range of speed of the motor 55 is also controlled by the variation of the coupling of the transformers 52 and 54. This may be discussed as though the motor were starting from zero. Neglecting for the moment the small plateau 222 which represents inching speed, the initial energization of the motor 55 from a start occurs by applying full field excitation with minimum armature current. Thereafter, to increase the speed, the armature current is increased along the line 218 from the plateau to the point 220 which is, of course, the base speed. The field remains fully excited during this portion of the characteristic, and hence its rotary transformer 54 will maintain constant coupling, while the coupling of the transformer 52 varies.

It should be understood from the above, that the contours of the cams 203 and 205 are worked out on the basis of the characteristics of the motor which is being controlled, for applying the proper pattern signals to the respective control channels. Compound wound motors which have more than two different zones of control for stop the press.

the characteristics of excitation versus speed can as readily be controlled by suitable choice of cam contours through the rotation of only a single shaft of the pilot motor.

The deceleration of the motor along the line 218 is identical to acceleration except that it occurs at a greater speed. This function is also known as reset The change ofk speed of the cam shaft 210 which is required for this can be accomplished by de-clutchng the pilot motor 50 and coupling another motor of different speed to the cam shaft 201; or could be accomplished through the shifting of gears of a gear train; but preferably is achieved through the use of a separate winding built into the pilot motor and used for driving the same at a different speed in the reverse direction.

The curve 219 is the emergency stop characteristic related to the scale 216. It has no relation whatsoever to the scale 214 because it functions independently of the rotary transformers. When suitable apparatus is actuated for an emergency stop, the excitation of the armature is removed and the dynamic ybrake is permitted to slow the motor down to a full stop. Various considerations of the apparatus control the rate of stop, including, the eicacy of the brake, the inertia and friction of the apparatus, etc.

The inching speed 222 represents a condition of excitation which is permitted to remain over a few degrees of rotation of the cam shaft 2tl1, such as for example for the purposesexplained above.

The pilot motor 50 performs other functions besides the programming of the excitation of the main drive motor or motors of the press. The fact that each position of rotation of the cam shaft represents a condition of excitation giving rise to a particular speed of the motor 55 (as well as any other motors being controlled by the master control), or a particular time in the cycle of control, enables the rotation of the shaft 201 to beused to open and close certain control switches in synchronism with the control cycles. For example, nine cams are shown mounted on the shaft generally at 235, and rotating therewith. Each cam operates a switch, there being nine switches as indicated at 224 to 232, each having a followeras indicated at 236. The various switches operate various circuits which are explained in the chart of FIG. 4 over the range of rotations of the cams indicated.` The solid bars represent switches closed, the open spaces represent switches opened, and the dotted lines represent ranges over which the switches can be adjusted to open. For normally closed switches the opposite is true. Thus, for example, the tension regulating device is operated from the position of 12 of rotation of the shaft 210 throughout the entire rotation thereof; the normally closed faster limit switch is opened only at the end of rotation of the shaft; the normally closed slower limit switch is opened during the first few degrees of rotation; the web severers can be adjusted to close at any time from about 106 of rotation to about 135 of rotation; etc.

The various functions controlled by the switches 224 to 232 driven bycams 235 are generally as follows:

The detector switches are energized after the press is moving at a good speed, say with the web travelling at a speed of yabout l0() feet per minute so that ifthe web tears or breaks, the detector circuits will automatically Breaks occurring at lower speeds are not as serious since they usually occur during testing or the like.

The web severers operate in conjunction with the folder for cutting the web during the assembly thereof into the final product and the equipment need not be operated until a higher speed is reached, the exact speed being adjustable.

Automatic web tensioning regulating equipment is placed into operation after the press gets moving and is operative during the entire range of speeds.

The faster limit switch determines the maximum speed ld at which the drive motor is permitted to operate and hence will not open until the upper speed limit is reached.'

The slower limit switch speed controls the rest position of the pilot motor 50.

The automatic acceleration limit switch stops` the pilot motor rotation when the press has reached a predetermined speed. This may or may not be the same as the faster limit speed.

The automatic deceleration limit switch is adjustable, and it enables the press to be decelerated automatically only if the press speed has exceeded a certain predetermined value.

The register control go-down relates the operation of the registration control equipment with respect to press speed. Obviously the registration control equipment should not be set into operation until the press is ready to be driven at a fairly fast speed, after all preliminary adjustments have been made.

The shunting contactor switch is normally open and is closed after base speed has been reached. The contactors involved are 164 in FIG. 3. They cut out the saturable core reactors 114, and 116, permitting the power to be applied to the rectifier 124 without passing throughy the reactor windings. Since the speed characteristic from point 220 to point 221 calls for maximum armature excitation, there is no need for control during this period, and in fact coupling of the transformer 52 is of little or no consequences during this range of speed. This arrangement eliminates hunting, uses less power, reduces losses in the reactors, and of course keeps the heat of the apparatus down.

The shunting contactors 164 need not be used, in which case the excitation control signal from armature control channel will be such as to permit the reactors 114, 115 and 116 to pass maximum current. v

Other switches and cams giving rise to additional switching operations can be provided. f

Attention isy now invited to the details of the assemblage shown in FIGS. 6 to 9 inclusive. These illustrate the pilot motor 50 and the rotary transformers 52 and 54 with their associated mechanical connections.

`The pilot assemblage which comprises the pilot motor 50 and all of the structure coupling the same with the rotary transformers 52 and 54,y as well as the switches 235 and the like are mounted on a suitable base, such as illustrated at 20.2. This base may be a part of the cabinets or panels housing the control gear or may be secured thereto. As previously mentioned, it is preferred that the pilot motor 50 have two independent windings operating the same inits forward or reverse direction, and obviously these cannot be illustrated in the drawings except by showing two symbolic inputs to the pilot motor in FIG. l. Any suitable reduction gearing can be used, which may include a suitable gear box furnished with the motor by the manufacturer in the same housing as shown at 204 driving a pinion 206 which in turn drives a larger gear 208 secured to the shaft 201. Actually the shaft 201 is journalled at 210 and 212 in suitable supports secured to `the base 252,' and makes its connection with the drive gear through a clutch 233 so that shaft 201 is rotated through suitable control circuitry associated with the system 60.

The side elevational view of the assemblage in FIG.k 6 best illustrates the arrangement of the elements. The top of the assemblage is provided with several terminal strips such as 234 and23'7, but the wire leads are not shown for purposes of clarity. The terminal strips234 may be mounted at the left hand end of the assemblage and be used in connection with the rotary transformers, and the strips 237 may be used infconnection with the switches 235 and perhaps other electrical connections.

The rotary transformers 52 and 54 are also secured to the base 252 and each has a rectangular plate 233 and 240 secured respectively to the outwardly facing end thereof. The strips 234 and 237 as well as the switches `to the shaft 213.

l 235 may be secured to elongate support brackets or structural elements 241 and 242 held in place on the plates 238 and 240 by suitable machine screws such as at 243 and on the support means 244 by screws 245. Each plate 238 and 240 is horizontally slotted, with the slot 246 provided in plate 23S and the slot 247 provided in plate 240. The follower 207 is actually a small roller mounted on the end of a rack 243 which is slidably mounted on the slot 246 and prevented from dropping out by a retaining cover plate 250 held on the plate 23S by suitable fasteners 251. The follower 209 is a similar roller mounted on the end of a rack 252 confined by the cover plate 253 held in place by screws 254. In each case the rack teeth are directed downward, and in each case the teeth mesh with a pinion gear mounted on shafts of the respective rotary transformers. The rack 24S meshes with pinion 255 mounted on shaft 211. The rack 252 meshes with pinion gear 256 which is secured In both cases, the shafts have spiral springs urging the shafts to rotate in directions which tend to force the pinions to push the racks in directions urging the followers against their respective cams. Thus, in FIG. 9, the spiral spring 256 is shown making a mechanical connection between the plate 240 and the shaft 213 to urge the shaft 213 in a counter clockwise direction as viewed in FIG. 7, which in turn urges the rack 252 to the left and the follower 209 against the cam 205.

Obviously the racks 248 and 252 and their respective pinion gears 255 and 256 are in different planes to align with the respective cams 203 and 205.

Any other suitable means can be used to bias the followers against their cams and still permit the rotary transformers to be rotated. As a symbolic example,*in FIG. 7, on the left hand side there is a bracket 258 secured to plate 238 and conning a helical compression spring 259 which urges the rack 24S to the right.

The exact construction of the pilot motor-cam-rotary vtransformer assemblage is capable of wide variation.

Primarily it forms means driven and controlled by the static control elements system to position both of the rotors of the rotary transformers at locations relative their respective stators such that the control channels will 4respectively receive pattern signal information directing the desired excitation of the armature and field of the drive motor 55 and any additional motors connected therewith.

A detailed explanation ofthe static control elements system follows: In the description, it should be appreciated that the elements which are discussed are for the most part static control elements or components, made up of small circuits which perform all of the cybernetic functions heretofore performed by means of relays and similar moving part components. Y

For this purpose, attention is invited to FIG. 5. Here the static control elements are laid out in a circuit which could be typical ofv a press drive control embodying the invention herein, providing all of the elements of control described above, and used in connection with the structure thus far described.

The static control elements which are preferred are.

those utilizing the circuits of Rainey Patents 2,717,965, 2,770,737 and 2,783,315 which have no moving parts and which are based upon circuits which use semi-conductor diodes and magnetic structures having substantially square hysteresis loop flux characteristics enabling them to occupy two completely different states of magnetization depending upon the direction in which polarized. The details of these circuits are known, and in recent years commercial versions have appeared on the market, including structures-manufactured and sold by Westinghouse Electric Corporation of Pittsburgh, Pennsylavina, under the trademark Cypakf In order to describe the circuit of FIG. 5, the cybernetic symbols which have become conventional should be explained. The symbol for an AND function is most output. A signal applied to ei-ther input will result in an output signal. The basic symbol for a NOT function is a rectangle with a small circle at its front end. There will be an output signal only if there is no input signal, and if there is an input signal there will be no output signal. The symbol for a MEMORY function is a pair of rectangles with two inputs on the left and one output. The small circles also are present on the input sides. The MEMORY elements provide an output when there is an input, instantaneous or otherwise, and discontinue the output when there is a second input. The symbol for a TIME DELA is a semi-circle, and there will be an output a certain time after an input signal has been applied.

n In the circuit, the symbols are designated in accordance with their functions. The AND symbols are designated A-1, A-2, etc.; the OR symbols are designated O-1, O-2, etc.; the NOT symbols are designated N-l, N-2, etc.; the MEMORY symbols are designated M-l, M-2, etc.; the TIME DELAY symbols are D-1 and D2. There are amplifiers illustrated symbolically as triangles and designated AM1, AM-Z, etc.

The static control elements are supplied with various voltages from the sources, such as through a transformer 260 the primary 261 of which is connected across the line, and the secondary 262 of which is connected to the static control element power supply 264 which provides the voltages needed such as 8, 15 and 23 volts direct current with a common return. The static control elements use polarized signals, related to the phase of the line voltage, notwithstanding that the power supply to the elements is D C. This is provided by reason of the relationship of the pulsing D.C. to the phase of line voltage. Accordingly, the power supply will provide these voltages of dierent polarities, and the polarities will be displaced by Note therefore, that the inputs and outputs of the static control elements of FIG. 5 are also polarized, the polarization being symbolized either by a or a 0. A signal cannot be received of opposite polarity, and this may be the basis for transfer of control to a second station, as described in my co-pending application Serial No. 729,200, led April 17, 1958, and entitled Static Control Switching Apparatus.

The phase sensitive characteristic of the static control elements is also useful as a gating means in logic circuits. For example, single input AND elements can be used to reject other than certain phase signals from multiple signal outputs. AND elements have opposite input and output Aphases as will be seen in the diagram. There are several triangles which are designated AN-1, AN-2, etc. These are actually combination elements made of AND and amplifier elements to give an increased amplitude signal output. They are equivalent, in the logic sense, to AND elements. The phase symbol illustrated on each of these is its input phase. Its output phase is the reverse.

The secondary winding 262 is also connected across the two bus conductors 265 and 266. A plurality of input transformer-rectifier combinations designated X-1 to X-12 are adapted to be connected across the bus conductors through switches or contact making devices which presently will be described. Various emergency and test apparatus interrupting the connections is not shown. The transformer-rectifier combination X-l is in series with faster limit switch 224, whose cycle of operation is described in connection with the chart of FIG. 4. This is one of the cam-operated switches mounted on the pilot motor assemblage adapted to be opened and closed through movement of the shaft 201. The output from the closing of the switch 224 appears at the conductor 265. The switch 225 is the slower limit switch, also camoperated as switch 224. It is normally closed on the 1.7 contact 266 and is open only for the short period before the press is started up, at which time the contact 267 is cngagedtoignite the lamj 263 to showy that the slower limitvswitchis open. Output appears at the conductor- 270.

The switch 226 is the automatic acceleration lirnit switch which is cam-operated and the function of which has been explained. lts output appears at conductor 272. Switchi227 is another cam-operated switch controlling the automatic deceleration limit, and its function has also been explained in connection with FIG. 4. The output of this switch appears at conductor 271. There are a series of switches and relays which are shown at 273, 274, 275, 276 and 277, and these are respectively the fail safe relay, the held loss relay, the feedback `control relay, a test switch, and an emergency switch. The closing of any of these will provide a signal through the transformer-rectifier combination X-S at the conductor 278, the purpose of whichit is to stop the press.

The other controls operating into the circuit are not automatically operated but comprise the manual buttons located on `the push button station 62, normally the master control panel. Note that each switch is shunted by a conductor leading to another station for parallelr or alterna-te control, depending upon circumstances which We need not discuss. This is shown at Switch 231 is the SAFE-READY switch which provides an output at the conductor 232. The switch 282i is the INCHING yswitch which provides an output through the transformer-rechner combination at the conductor 28d. The switch 255 is the SLOWER switch operating through the transformer combination X-ti to place a signal at the conductor 286. The switch 23'/ is the FASTER switch which provides an output signal .through the transformer-rectilier combination X-9 at the conductor 23S. The switch 289 is the STOP switch which provides an output signal at 296i through the transformer- Lrectilier combination X-lt). Switch 291 is the AUTO- MATlC DECELERATlON switch and its outputis at 292. Switch 293 is the AUTOMATCv ACCELERA- TlON switch and its output signal appears at 294..

The operation of the various parts of the circuit will now be explained.

yThe SAFE-READY switch 281 has two buttons, one of which is referred to as SAFE and the other as READY Both operate on the same switchthe one to close the switch which'will automatically latch itself in this position and the other to open it, that is, release the latch. When the SAFE button is depressed,y the primary winding of the transformer-rectifier combination X- is energized by 115 volts AC. and the output of the combination is a full wave rectilied ysignal whichV appears at the conductor 282. This lead 282 is connected through the conductor 2% to the amplier ANI-15 to a relay 297 which closes a'contact to green lights at suitable locations (not shown) on the press to inform the operators that the SAFE `button has been depressed providing the sate condition represented thereby. The arnplier AM-lt), as well as the other amplifiers Alvi-4 to AM-lll inclusive, all obtain their power from` a full wave rectifier 29S supplying direct current over the buses 299 and 300 and energizing the relays which will be described, the relays being connected between the amplifier' outputs respectively, and the bus 300. Rectiiier 293 is powered through transformerk 269.

The signal from the depressing of the SAFE button is also applied to three other static control elements, namely-the OR element O-3, the OR element O-7 and the NOT element N-3.

The OR element O-7 has the signal applied thereto through the conductor 361 .and applies `an output to the lead 392. -Conductor 302 in turn applies a signal to another OR element O-2. It will be recalled that the conductor 272 was provided with an output signal from the switch 226, the AUTOMATIC ACCELERATEON lli) ing the circuit, and have no signicance LiMlT switch, and hence there will be an output from the OR element O-Z if either the switch 226 is closed or theSAlT'E button is depressed. This output appears at the conductor 3% and applies the signal to still another OR element O-S, providing an outputat the .conductor Stift. Since the original signal was a full wave rectiiied DC., the signal at 3M is still full-wave, and the signal applied to the lower section of the MEMORY element lvl-2 will be accepted by the pinput of that section. This will hold the MEMORY element IVI-2 in an oit state, and prevent an output from appearing at the conductor` 39S. y signal. (Hereinafter the upper and lower sections of the memory units will be designated by the sufiix U or lL -following their character references, such as for example, M-Z-U is the upper section of MEMORYelement M-2, M-Z-.L is thelower section of MEMORY element M-Z, etc. These designations are only to be used in considerphysically upon the actual structures.)

The signal onconductor 3h55 is adapted to be applied nrough the OR element O-ll to the conductor 366 to the middle 0 input of the AND yelement A-S. The qb output of the AND element A-S is connected by the conductor Sii? through the ampliiier AM-l to the krelay 3%. This reiayt is the faster pilot relay, and when it is energized, yit connects the forward driving winding of the pilot rnotor titl to a source of power such as to rotate the shaft Ztli in a direction to increase the speed of the drive motor d5. Obviously, when the SAFE button 2il is depressed and held down by the mechanical latch thereof, there can be no 6 signal output from the MEMORY element ivi-2 and the relay 393 cannot be energized.

ln addition to the above removal of an input to the center 0 input of the three channel ANDl element A-S, there is an additional safetyfactor to prevent the energizing of the relay 3tlg. As noted above, the signal on depressing the SAFE button 281 is also applied through conductors 2t2, 361 to the NOT element N-3 by way of the conductor fait?. This signal being fully/ave, it is accepted by the 0 input of the NOT element N-3 and removes the qb output signal from the conductor 316. Referring to the OR element O-11, it will be seen that the lower input was also capable of producing a signal at the conductor Fitto. This signal to O-ltl is obtained as the output of the three channel AND element A-S on the` conductor 311. Since the three inputs to the AND element A-S includeas` the top input a connection 312 with the conductor 31), it there is no signal output ronithe NOT .element N-S, there will be no 0 signal at 311 and again no output at Sile so that relay 368 cannot be energized.

in passingit will be noted that all transformer-rectifiers produce full wave outputs having both q and 6 pulses.

The third application of the signal output from the transformer-rectier combination X-o through depression o the SAFE button 281 is to the OR element O-3. From the element O-l, the signal is applied by way of the conductor 3113 to the OR element O-l. The ot er signal which is applied to the `OR element O-l is by way of lead 27@ to the upper input from the transformer-rectifier combinationV X-2 which occurs whenr the slower iisnit switch is closed to its bottoni` contact 26e. The OR element O-l output is applied to the input of the NOT element N-lwhich removes the 6 output signal from the conductor 315. This conductor 315 applies one of the inputs to the two channel AND element A-2 which supplies a signal to the upper input of kIVEMORY element lVl-l by way of they conductor 31o. The upper section M-fi-U has a c input which can be provided by the output of A-Z, and it in turn can provide a g5 output at 31.7 which passes through the single channel AND element A-d, which serves as ya phase gate to the conductor 31S. This conductor is adapted to apply a signal to amplitier ANI-7 which This output would comprise a 6 i energizes the relay 319, the line contactor relay by means of which the press drive is energized. With the output signal at 315 gone, there is no output signal at 3M, and there must be a signal at the q input of M-d-U to turn on the MEMORY element M4. If the MEMORY element had been in its on state, the removal of the signal to its upper input would not have changed it to olii Without a signal output from the MEMORY element M-d, the line contactor relay 319 cannot be energized. This results again from depressing and holding the SAFE button. The significance of the system is that if the motor S5 were not already running, the depressing of the SAFE button Zll would thereafter prevent it from being started because the line contactors could not be closed.

Another function is performed by the depression of the SAFE button 281. The output of the AND element A-2 which was removed when the SAFE button was pressed is also applied to a conductor 32) that comprises one of the inputs to a two channel AND element A-7. This AND element applies a 6 output by the conductor 321 to one of the inputs of the OR element O-ll, the output of which is at 322 and is applied to amplilier AN-3, conductor 323 and ampliiier AM-S to energize relays 324 and 325. These are the run relay and the run light relay, the latter providing a signal to show that the run relay has been energized. The run relay is connected to energize the pilot motor to provide inching speed, and hence, with the SAFE button depressed, there can be no output at 321 and no inching of the press. The INCH switch 233 provides an output from the transformerrectifier combination X-' at the conductor 234 which goes directly to the lower input of the AND element A-7.

Attention may be given at this time to the FASTER button 287, the depressing of which will apply a signal through the transformer-rectifier combination X-9 to the conductor 288, which in turn places the signal at the upper input of the OR element O-S through conductor 326 and to the central qb input of the AND element A-3 by way of the conductor 327. It is desired that the depressing of the FASTER button does not start the press or increase its speed if already running when the SAFE button 231 is depressed. Since the upper input of the AND element A-3 is already removed, adding a signal in the center channel will have no effect on the faster pilot relay 333. The depression of the FASTER button 287 also provides a signal in a manner which will be described hereinafter, by way of the conductor 326 through OR element 0 5, conductor 327, OR element O-ti, conductor 328, MEMORY element M-S, conductor 329, gating AND element A-S, conductor 330, time delay element D-ll, conductor 331, MEMORY element M-S, and conductor 332 to the lower input of the AND element A-2. As explained, when the SAFE button 28T is depressed, there is no input to the upper channel of the AND element A-Z, and hence the signal received from MEMORY element M-S is without efect.

It becomes apparent from the above description, that the use of the SAFE button is quite versatile since it renders the press completely safe to work on by preventing its starting if it has not been started and by locking the speed of the press to the speed it has if the press is running when the button is depressed. The logic functions are all performed by means of the static control elements described, the final connections being achieved through simple relays energized in response to the logic commands ofthe system.

The other command button affecting speed of the press is the AUTOMATIC ACCELERATION button 293, and this button cannot change the speed of the press when the SAFE button has once been depressed. The closing of the switch 293 applies a signal to the conductor 2.94 through the transformer-rectifier combination X-12 which in turn applies the signal through conductor 333 to the bottom input of the OR element O--6. We have already seen that the FASTER button 237 was unsuccessful in increasing the speed of the press by means of a signal applied to the OR element O-6, and hence the ANTOMATIC ACCELERATION signal cannot do so either. The signal of conductor 294 is also applied' by way of the conductor 334 to the upper input of the AND element A-l which, even were there a a input on lead 335 such as to combine with input of lead 334 to provide a 0 output at conductor 336, would be of no avail so long as there is a signal at M-2-L'. It is noted that the presence of both inputs on a MEMORY element will provide no output. Thus, with the SAFE button 281 depressed, it is impossible for the faster pilot relay 303 to be energized.

The functions performed by the SLOWER button 285, AUTOMATIC DECELERATION button 291 and the STOP button 239 can be carried out notwithstanding the depression of the STOP button. This, of course, is consistent with the concept of rendering the press safe to operate and work on, since each of these buttons tends to bring the press to a stop.

The SAFE-READY button has a mechanical latching arrangement which keeps the button in SAFE position, once depressed. The latch can be released by the operator, such as by pressing a button or lever (not shown) which is usually marked READY. This removes all of the signals at conductors 282, 2%, 391, and 309, and along therewith removes all of the conditions provided by the SAFE button, described above. The removal of the signal from the input to the NOT element N-3 restores signal at 310 which now appears at conductor 337 and is applied through OR element O-lS, conductor 338 and amplifier ANI-9 to energize relay 339 which lights red warning lights to inform the operators that thepress is in readiness to operate. Removal of the signal from the conductor 296 extinguishes the green safe lights 297.

The line contacter relay 319 may originally be operated, as will be seen, by either the INCH, FASTER or AUTOMATIC ACCELERATION push buttons 283, 287 or 293 respectively. The energization of this relay (or relays) will light suitable indicating lights on the master control panel, at the station where 62 is located and elsewhere if desired, and also provides 220 volts A.C. to the line contactors M1413. The INCH button will not de-energize the line contactors when used to start or stop the motor, but the STOP button 289 will do so.

When the pilot motor is in reset, that is its initial position, the switch 225 is open (see chart of FIG. 4, SLOWER LIMIT). There is at this time no signal at conductor 270, and if the SAFE button 281 has not been depressed, there is no signal on conductor 313. With no' output from OR element O-l on conductor 314, there will be an output from the NOT element N-l at the conductor 315, and this is applied to the upper channel of the AND element A-2. The lower channel of the AND element A-Z has an input from the conductor 332 and hence the two inputs to A-2 will provide an output at 316, when a signal is provided on conductor 332 from the signal and delay circuit designated generally 340. If this delay and signal circuit is not in the system, the signal comes from the OR element O-6 directly.

The signal at the lower channel of AND element A-2 is produced whenever any one of the buttons 283, 287 or 293 is depressed. The latter of these, the AUTO- MATIC ACCELERATION button provides a signal at 333 to the OR element O-6 which passes through the signal and delay system 340 to the AND element A-2,

The INCH button 233 provides signal on conductor 341 to the OR element O-S which in turn provides signal at 327 to OR element O-6. The FASTER button 287 also applies its signal by way of the conductor 326 to 0-5.

The AND element A-Z has an output at 315 when both channels have inputs and this is applied to M-Ll-U, being a e signal. This signal will turn MEMORY unit M-4 to on condition, providing a qs output state in conductor 'Ztl 3ll7. This passes throughthe qi gate A-4 which pas/ses through the amplifier AMJ? to energize the line contacter relay 319. p

From the above it will be seen that any push button which calls for press movement can close the line contactor relay Fili?, but this is true only when the piloty motor is in reset condition.` It will be recalled that it the pilot motor` and its shaft lhll are not in reset position, the switch 225 will be closed, there will be a signal Vat 27d, a signal at 3M, and the NOT element N-l will remove the signal from the conductor ST5 and there will be no output from the AND element -2.

The functions of the INCH button 283 and the FASTER button 287 will now be discussed. As understood from above, either of these can energize the line contacter relay 319 from reset position of the pilot assemblage. In'addition, the INCH button 2ls3 provides a signal at conductor 28d which is an input to the AND element A-7. Since there is a signal at 320 when the pilot assemblage is in reset condition, there will be an utput from the AND element A-'' at 321. This will energize the run relay 324 through the OR element O-ld, the conductor 322, the AND element AN-3, conductor 323, and the amplifier AM-S. When the line contactors are closed and the run relay is closed, sufficient power will be supplied to the armature 56 to start the motor 55. Release of the INCH button 233 will 'stop the motor. The movement of the pilot motor 5t) is such as to bring the operating point of the drive motor 55 onto the small plateau 222 (see FIG. 4) to a slow speed, the character of which can be built into the system in a manner whichr is believed understandable from the description ythus far.

When the INCH button 283 is released, the signal on the conductor 284 is removed and hence the relay 324 is de-energized- This will not ailect the line Contact relay M9, since this relay is energized and continued to be energized by the output of the MEMORY element M-4. 3M is an optional inching bralte relay. i n y If thefINCH button 233 had not been pressed from reset position of the pilot assemblage, the line contacter relay 319 would not have been energized, but the pressing of the FASTER button 287 would have do so, as previously explained. Furthermore, the line contacter relay would remain energized thereafter, just as in the case of the pressing of the INCH button first.

Pressing the EASTER button 2&7 applies a signal t0 the center input of the AND element A-3 by Way of conductors 238 and 327. Since the upper input has a signal becausey the READY button is pressed, and the lower input has a signal through the signal and delay systemy 34) from the AND element A-2, permitted because of the signal from NOT element N-1 due to the SLOWER LIMIT switch being open, there will be an output at conductor 3M which willplace a signal to the center input or" the three channel AND element A-S. This signal is also applied by way of the conductor` 342 to the MEMORY element M-7U which places this memory element in on state, providing a 0 output at conductor 343 which passes through the OR element @-14 in a manner previously described to energize the run relay 32d and its warning light relay 325. Another relay, namely the run tensioning relay 344 may simultaneously be energized through the conductor 345, one input AND element AN-i, conductor 346 and ampliiier AM-3. This v circuit is in broken lines to show that it is optional at this point. f

The momentary closure of the FASTER button 287, it will be recalled, energized the line contacter relay 319 and turned on the MEMORY element M-' to maintain the run relay 324. The energization of these two relays provides a continuous or threading speed of the press, in any event, if the FASTER button had momentarily been depressed and released. -K

It it is desired to run the press at a faster speed, increasing it continuously, but at a controlled rate without the increase following any predetermined automatic pattern, the FASTERfbutton may be held depressed-as long as desired. As soon asgthe button is released, the speed attained will be constant until further control is exerted. When the FASTER button 237 is depressed, there will be a continuous signal output at the conductor 327, and presuming an input at the upper and lower inputs of AND element A-3, there will also be a continuous signal at conductor 396. The FASTER LIMET switch 224 is normally closed and hence provides a signal on the conductor 255 through the transformer-rectilier combination X- which provides an input at the upper channel of the AND element A-. is no signal from the SLOWER button 23S. rThis causes the NOT element N-li to provide an output at conductor 347 which is 0 and the AND element A-S having all three inputs now energizes the faster pilot relay 308. This energizes the faster winding of the pilot motor Si) to rotate the shaft Ztll in ya direction to cause the drive motor 55 to increase speed. Suitable warning lights can simultaneously be energized. It the EASTER button 2W is released, the signal from AND element A-3 drops out and stops the pilot motor. Note that when the maximum speed is approached, the FASTER Lik/HT switch 224 will be opened by its cam 235 and de-energize the relay 363 to stop rotation of the pilot motor 5t).

Another control function which will tie-energize the relay 308 is the pressing of the SLOWER button 285 which applies a signal to the NOT element N-4 and rcmoves the lower input to the AND element A-S.

The next control function which will be described in detail is the manual decrease of speed of the press by pressing the SLOWER button The SLOWER LIMIT switch 225 must beclosed for the SLOWER button 285m accomplish any function, vand hence the press must be running at some speed which results from the cams 203 and Ztld (FIG. 7) being in a position in which the shaft Zilli and a cam 235 have closed said switch 225.

When depressed, the SLOWER button 285 applies a signal through the transformer-rechner combination X-S to the conductor which provides an input to the OR element 'O-9, an output on conductor 34S to the'OR element O42 and a signal on conductor 349. This provides an input signal to the upper channel of the two channel 6 AND element AN-ll. The lower channel of AN-l receives its signal on conductor 35i) which connects with conductors 351 and 27h to the SLOWER LIMIT switch 225. If above the lower limit, this switch will be closed and a signal will be provided at 350. Since AN-l has both or its input signals there will be a o output on conductor 352 through amplier AM-S to ener-V gize the slower pilot relay 353 which in turn supplies an AC.` drive voltage to the slower ywinding of the pilot motor 5h to drive the shaft 261 in' a direction to decrease speed of the drive motor 5S. Suitable indicating lights can simultaneously be energized.

If the SLOWER button 285' is kept depressed, the press will run slower and slower. Any speed attained will be maintained if the SLOWER button is released. When the lower limit has been reached and the SLOWER LIMT switch opened, the lower input to the AND element AN-1 will be removed and further control is removed from the SLOWER button 285.

The SLOWER button does not affect the line contacter relay 319 or the run relay 324, but it takes control from the FASTERbutton 287 by supplying an output from AND element AN-ll on conductor 355 to the NOT element N-l which cuts oit the lower input on 347 to the AND element A-8 to prevent energization of the faster pilot relay 308. f

The STOP push buttontil isa control by means of which the press can be brought to a complete stop in as short a time as possible. Pressing this button provides a signal on conductor 29h to inputs of the OR elements O-3 and O-rl. Output of 0 4 on conductor 355 and 356 Assume for the moment, thatl there turns oif the MEMORY element M 7. The oit state of this element is a p output which when passed through OR element 14 will not be accepted by 0 AND element AN-3 and hence will remove input to amplier AM-S and de-energize the run relay 325. A signal is also applied to MEMORY M i-L to provide an off state 0 output which is not acceptable to the qb phase input'of AND element A 4 so that the line contactor relay 319 is de-energized.

The line contacter relay is a time delay opening type of relay and hence the line contactors will remain closed for the time of the delay. Since the run relay 324 is closed, however, there will be no direct current on the control windings of the reactors illl, 115 and M6 and the A C. will return these reactors to desaturated state.

If the STOP button is pressed while the press is operating at higher than threading speed, there are other functions required to be performed to bring the press to a complete stop. The signal on the conductor 355 is also a signal on conductor 357 which provides an input to MEMORY element M 3 U which turns the element in on state with a 0 output at conductor 358. This passes through the OR element O lZ as a 6 signal and, applied to AND element AN 1 along with the signal from the switch 225, operates the relay 353 to energize the slower pilot motor winding until the pilot assemblage is reset, which opens switch 225. Since signal output from MEMORY element M-3 continues, even after the STOP button 289 has been released, it follows that every time the STOP button is pressed, the pilot assemblage will be driven to reset condition and stop there. Furthermore, when reset condition is reached and the switch 225 opened, signal on conductor 35i will be removed, NOT element N 2 will have an output on conductor 359 which connects with M-3-L placing the MEMORY element M-3 into off condition with a qb output unacceptable to AND element AN-l.- This therefore resets the MEMORY element M 3 to a State which does not interfere with operation of the press, but is available to reset the pilot motor 5) when the STOP button is once more presssed.

The removal of the signal output from AND element A 4 provides an output from the NOT element N 5 to the phased two channel AND element AN 2. The second input to the AND element AN 2 comes by way of the conductor 360 as a p signal from the output of AND element AN-l which had been providing the signal energizing the slower pilot relay 353. The output from the AND element AN-Z appears at conductor 361, passes through amplifier AM-6 and energizes the dynamic brake relay 362 and the field drop relay 363 both of which function to bring the motor S5 to a stop as rapidly as possible. The dynamic brake relay is energized until the pilot motor 5t) is driven to reset.

In the event that the pilot motor 50 is being driven in a faster direction under the control of the automatic acceleration circuit, which will be explained, the STOP button 289 must provide a signal to remove this control. This is done by the signal output from the STOP button being applied by way of conductor 290, OR element 0 4, conductor 364, OR element O conductor 302, OR element 0 2, conductor 363, OR element`O 3 and conductor 304 to MEMORY M 2-L. This turns MEMORY M 2 to off state, with a qb output not acceptable to the AND element A S, which will de-energize the relay 303. As seen below, the AUTOMATIC ACCELERATION button 293 can turn the MEMORY element M-2 to on condition for automatic increase speed operation of the pilot motor 50.

The STOP button, as stated, closed the dynamic brake relay 362 which closed the dynamic brake contactors. There is also a normally closed interlock on the line contactor which is operated when the line contactors open after their delay as explained above. The desaturation period of the power reactor absorbs the initial shock of the transfer from the press being driven to its being braked 2.4 to a stop. The relay 362 is also a time delay opening relay to maintain the dynamicbrake contactors after the pilot assemblage has been reset until the press has come to a complete stop.

The effects of pressing the AUTOMATIC ACCELERA- TION button 293 to some extent has been mentioned above. The purpose of this button is to bring the press up to its maximum speed along the characteristic 21S (-see FIG. 2) as rapidly as possible and without the need for holding the button 293 depressed, either-from a condition of reset or from some speed at which the press may have been running. It has previously been explained that the signal output at the conductor 294 can energize the line contactor relay 319 under certain conditions which would usually obtain when the AUTOMATIC ACCEL- ERATION button 293 is depressed. The signal output from X-12 on 294 is also applied by lead 334 to the upper input of AND element A l. The secondinput to the AND element A l is applied by way of lead 335 from the MEMORY element M 4, which, it will be recalled, is required to be in on state in order to provide an output to energize the line contacter relay 319. The 0 output at 336 turns on MEMORY element M 2 which applies a signal on 305 through OR element 0 11 to p rovide the center input to the AND element A The other two inputs to A S being present, there will be a signal output on 307 to energize the relay 308 through the amplier AM-i.

Turning the MEMORY'element M 2 to on state maintains the energization on the faster pilot relay 308 until this memory element is turned off or one of the other inputs to AND A S is removed. if the slower pilot relay 353 is energized during automatic acceleration, as by pressing the SLOWER button 285, there will be an output from the AND element AN-l applied by way of the conductors 360 and 365 back to the OR element 0 8 applying an input at 304 to M 2 L which turns off the MEMORY element M Z. Since this state is retained by the MEMORY element M 2, discontinuing the application of signal to the slower pilot relay 353 will have no effect on the state of MEMORY element M 2 so that automatic acceleration will not be resumed. This is an obviously safe procedure since it prevents the press from moving at a rate faster than that which obtains when a slow down signal is discontinued.

The automatic acceleration limit switch 226 operating through the transformer-rectifier combination X-3 is normally open. When a preselected speed is reached, represented by a certain rotational disposition of the shaft 201, the cam 235 closes the switch 226 and a signal is applied at 272 to OR element 0 2. The output from the OR element 0 2 at 333 is applied through OR element 0 8 to conductor 304 which places MEMORY element M 2 in an off state and hence cle-energizes the faster pilot relay 308.

The pressing of the AUTOMATIC DECELERATION button 291 serves to slow the press down at an automatic rate along characteristic 213 not requiring the button to be kept depressed, and under normal non-emergency conditions.V The speed will decrease to some value which is determined by the automatic deceleration limit switch 227. This switch is normally open, but is closed when the lower limit of speed is reached, due to the rotational disposition of the shaft 2M operating a cam 235. At all points above the minimum setting, there is no output on the conductor 271, and no input to MEMORY element M l-L. The pressing of the AUTOMATIC DECELER- ATION button 291 applies a signal through the transformer-rectifier combination X-ll to lead 292 to MEN'- ORY element M 1 U to place this element in on condition, providing a 0 output on the conductor 367 to OR element 0 9, the output of which provides an input to the AND element AN-l through the conductors 348 and 349 and OR element 0 12. Since for speeds faster than the lower limit, the switch 225 is closed, there will also speed at this time will be maintained.

lf the press is moving at a speed which is above the slower limit but below the automatic deceleration limit, pressing the AUTGMATIC DECELERATN button 291i will supply both inputs to MEMORY element M-l, and as previously explained, with both inputs applied to Va memory element there willbe no change in its output,

hence no command signal will pass.

The various signallights that: arekusually associated with a press can be installed and operated in parallel with the several relays, with contactors and the like to signal the condition of the press. The SAFE and READY conditions have been explained. The usual convention is that the SAFE condition is represented by a green iight, and the READY condition by a red light. Usually there are SAFE buttons at several stations, and the significance of the green light would be that the control pilot assemf blage is in reset condition, and at least one of the SAFE buttons at some station is depressed.y The red light would means that there is no SAFE button depressed at any station, but the control pilot assemblage may be in reset position or the press may be running. ln order to give better information, a combination of red and green lights can be used to notify the operators that the press is running, but has been locked to some speed by depression of a SAFE button somewhere. This is done by applying the signal from the AND element AN-S by way of the conductor 368 through the OR. yelement (1t-l5' to the amplifier Alvi-9 to energize the ready relay 339 while the run relay is energized, even though the other signal to the OR element O-lS is removed by depressing tle SAFE button.

lt will be noted that there is affail-saie circuit which returns ythe pilot to reset condition in emergencies operating through transformenrectiler combination X-S by way of conductorZS to OR element 4 to function as though the STOP button 239 were depressed. Other relays and switches perform similar emergency functions in parallel with the inail-safe relay 273.

Mention has been made of thedelay and signal circuit 349 which is another safety measure that is automatic and can be embodied in a system. This is an arrangement which works in conjunction with the controls that start up the press to provide a warning and also to require some action to be taken in a given time in order to achieve the movement. Simply stated, when the operator decides to start the `press and presses one of the three buttons INCH, FASTER or AUTOMATIC AC- CELERATE, there will be an alarm sounded, and this will continue for a short time, say three seconds. As soon as the alarm has stopped, the press will be operative, that is, capable of being started for another 'short time by the FASTER or AUTOMATIC ACCELERA- TlGN buttons. The operator must again pressthe starting button within this short time, or the entire process must be gone through. The operator is thus required to press the button twice or the `press to run; there will be an alarmffor the iirst period; and if he has changed his mind or learned of adverse conditionsto operationk in the meantime, he need not press the button after the alarm, and the press will remain in its quiescent condition.

The manner in which this is accomplished by means or the static control elements` is described hereinafter.

Pressing the buttons 283, 237 or 293 will, besidcs'any other function performed, apply a signal on the conductor 32S and place the MEMDRY element lvl-5 in on state. The on state is a fp signal which appears at 32%, passes the gating AND element A-S and appears at lt energizes the alarm relay 369 through the conductor Sl'tl and the ampliiier Ahi-lll. So long as the MEMGRY element MLS' is on, the 1alarm relay 369 will be energized. The same signal at k3Std turns on the "Elli/iE DELAY elements D-l which may be set 1for three seconds. After the three seconds have passed, the signal from the "DIME DELAY element appears at and places lt/iElt/lORY element l --3 in on condition. r.this provides the output signal on conductor 332 which has been mentioned previously. The delayed output signal also is applied by the conductor Sl to the OR element O-ld and the output of this element appearing at conductor 372 resets the MER/GRY element M-S to oit and hence the signal output to the alarm relay dell. The press has in the meantime been rendered operative through the AND element A-Z. f

This same signal on 371 applies a signal by way of conductor 373 to the MEMRY element M-t to place same in on condition providing a 0 output to the gating AND elementA-d and starting the TIME DELAY element D-Z.

At the end of a given time, say three seconds, there will l be a signal output from the TIME DELAY element D-.Z which passes through the OR element O-lt and this signal at the conductor 3M will place MEMORY element M-S in olf condition, removing the signal from the conductor 332 lf the press has not in some manner been started in the meantime, it cannot now be started without the lower input to AND element A-Z. Since the run relay must be energized to run the press, the signal which operates it out of the AND element AN-3 is used to reset the MEMORY element M-6 by way ot conductors 36d and 375. Since the FASTER button 237 and the AUT@- MATIC ACCELERATlN button 293 start the press tluough the AND elements A-3 and A-li respectively, and these elements require an input controlled by the delay and alarm system, it will be seen that the buttons must be pres ed during the second three second period to start the presses. L@nce moving, the delay and signal circuit does not affect the press.

Gnly the alarm portion of the circuit 3d@ is used with the lNCH button 253. Keeping the INCH button depressed delays the time that a signal will appear at 332 while sounding the alarm. Since the lower signal input to AND element A-'' is being provided directly from the lNCH button 2233, yas soon as there is an output from MEMORY elementflt/i-tl to AND element A-Z, the run relay 324i will be energized as well as the line'contact relay, and the press will start. Signal from conductor 375 keeps MEMRY element lvl-d in oil condition, preventing M-tl from being turned oir.

The STG? signal or reset of the pilot assemblage will turn oiMEMORY elements lvl-5 and M-S at any time by way of conductor 376.

Not a great deal has ybeen said about the manner in which the invention can be applied to typical installations, primarily because the nature of the invention is such that practically any kind of rotary press can advantageously use the drive hereof. The discussion which follows is in the nature oi a conclusion, describing generally the manner in which the invention may be used in different installations. .j

The described apparatus could be considered that required for a basic installation. This is shown in FlG. 10 diagrammatically. None of the power sources is shown. The block 38d at the right represents the control unit of a minimum installation, and as noted, it is formed of several sections shown symbolically as rectangles. The enn tire structure of the block diagram of FIG. l is contained in the block, with the exception or the motor and some other apparatus such as the detectors 66 and some of the safety apparatus associated with the press itself and the motor. The block thus includes the push buttons 62, the 

1. A PRESS DRIVE WHICH COMPRISES, A DIRECT CURRENT MOTOR COUPLED TO THE PRESS AND HAVING SEPARATELY EXCITABLE ARMATURE AND FIELD OF WINDINGS, SEPARATE MAGNETIC REACTIVE MEANS FOR EXCITING THE RESPECTIVE WINDINGS, CONTROL SIGNAL PRODUCING MEANS FOR VARYING THE OUTPUTS OF THE RESPECTIVE REACTIVE MEANS IN ACCORDANCE WITH PREDETERMINED PROGRAMS, A FIRST AND A SECOND INDEPENDENT AND SEPARATE CONTROL CHANNEL RESPECTIVELY CONNECTING EACH OF SAID REACTIVE MEANS WITH SAID CONTROL SIGNAL PRODUCING MEANS, EACH CONTROL CHANNEL HAVING MAGNETIC SIGNAL REGULATING MEANS THEREIN, A PLURALITY OF MANUAL CONTROLS FOR CHOOSING SAID PROGRAMS, AND SAID CONTROL SIGNAL PRODUCING MEANS INCLUDING A STATIC CONTROL ELEMENT CIRCUIT ENERGIZED BY SAID MANUAL CONTROLS. 